CN101848940A - Ternary mixed ethers - Google Patents

Abstract

The invention relates to innovative cellulose derivatives with low surface swelling in aqueous suspension, with high relative high-shear viscosity, and with high thermal flocculation point in water, and also to their use in building-material systems.

Description

Ternary mixed ethers

The derivatived cellulose that the present invention relates to innovate, also relate to them in dispersion bonded material of construction (dispersion-bound building-material) system, the preferred purposes in dispersion bonded lacquer (dispersion-bound paints), described derivatived cellulose has the low surperficial swelling in waterborne suspension, have high relative shear viscosity, and have the high hot flock point in water.

Because character that they are outstanding and their physiological safety; derivatived cellulose is used in multiple application; for example as thickening material, tackiness agent, tackiness agent, dispersion agent, water-holding agent, protective colloid and stablizer, and as suspension agent, emulsifying agent and membrane-forming agent.

The field that derivatived cellulose is used is their purposes as thickening material in emulsion paint.The viscosity of emulsion paint depends on shearing rate usually, and viscosity increases with shearing rate and reduces.When different derivatived celluloses is compared, be viewed as usually, the value of the mean chain length of cellulose chain is big more, and the reduction of viscosity that depends on shearing rate (shear-rate-dependent) in using the emulsion paint of their thickenings is big more.Therefore, when using the long chain cellulose thickening material, be usually less than those the cellulosic situations that have than the staple cellulose chain length of using in the viscosity (shear viscosity) of high shear rate.

As the emulsion paint thickening material, the particularly Natvosol (HEC) that in emulsion paint, uses, but: methyl hydroxyethylcellulose (MHEC) or methylhydroxypropylcellulose (MHPC).

Under the condition of the suitable selection of substitution value, MHEC and MHPC are insoluble in the hot water, and thereby can be by use the hot wash purifying, to remove salt and other water-soluble by product in their preparation process.On the contrary, HEC dissolves in the hot water, and thereby can not use the hot water purifying to remove salt and other water-soluble by product.

When using these derivatived celluloses, the program that the user often adopts is: at first prepare the suspension of derivatived cellulose in water, then with other component blending of itself and paint formula.For this purpose, the dispersion of derivatived cellulose must be can stir and pumpable.

Therefore, derivatived cellulose does not have spontaneous thickening power by contacting with water, and they adopt usually and postpone the dissolving preparation to be used for emulsion paint.

This postpones dissolving usually by for example adopting the temporary transient crosslinked means of dialdehyde such as oxalic dialdehyde to cause.As crosslinked result, it is non-water-soluble that derivatived cellulose begins, but is dissolved in the water as the function of temperature and pH of suspension, has thickening power then.

Except postponing dissolving, but the water of derivatived cellulose absorbs agitatability and the pumping that also influences derivatived cellulose suspension.In the present context, water by derivatived cellulose surperficial swelling and by the derivatived cellulose physical bond, and do not have derivatived cellulose to enter in the solution.Under a kind of particular case, if the surperficial swelling height of derivatived cellulose, then the water of whole amounts of suspension can be combined, but and lose the agitatability of derivatived cellulose suspension and pumping.

Although the form that postpones with dissolving provides common MHEC, however their strong swellings in waterborne suspension.But therefore after the short like this time, just lose the agitatability and the pumping of MHEC suspension.The HEC that uses in emulsion paint satisfies and postpones dissolving and the low relevant requirement of surperficial swelling in waterborne suspension, still has other shortcoming, for example above-mentioned in hot water solvability and below the other shortcoming pointed out.

Really be that the surperficial swelling of MHEC can be subjected to the additional treatment step influence subsequently.Therefore, for example, JP 48-34961 has described the thermodynamics processing that lasts the product of 4-15 hour time at 50-200rpm at 60-130 ℃ in the mixing vessel of sealing.Yet this handles operation, and correspondingly extra means cost and the complicacy with high is relevant, and relates to many extra times and energy.

The user of derivatived cellulose is high shear viscosity for another requirement of emulsion paint thickening.The viscosity of emulsion paint is not constant, but changes as the function of shearing rate.Along with shearing rate raises, viscosity degradation.In practice, this effect is clearly, and reason is under static state, and for example in jar between the shelf lives, high viscosity value is represented the character of emulsion paint, thereby supports about the filler that exists and the settled stability of pigment.On the contrary, in the process of processing with higher shear with roller or brush, significantly lower viscosity number is represented the character of emulsion paint, thereby allows quick and be easy to process.At this, be called shear viscosity in the viscosity of high shear rate.Yet shear viscosity must be only low, because otherwise the independent coating of lacquer does not produce enough coating thicknesses.In addition, under the situation of too low shear viscosity, lacquer splashes and may be formed into the degree of increase.

If only by changing the amount setting as the concrete derivatived cellulose of thickening material, then the user is not independent of the possibility of total flow behavior setting shear viscosity of emulsion paint to the viscosity of emulsion paint.Higher amount has improved shear viscosity, but generally, as a result of, it is too sticking that emulsion paint may become, and no longer has good working properties then, and reason is that for example levelling property becomes too poor, and thereby can not get excellent surface on the coating.

In the prior art, exist in the various known method that improves shear viscosity under the condition that does not make emulsion paint totally become too sticking.They comprise being used in combination of derivatived cellulose and synthetic associative thickener, with the use of associative thickening derivatived cellulose, other component that the activity of synthetic associative thickener and the activity of associative thickening derivatived cellulose are subjected to emulsion paint for example tensio-active agent greatly influences.This makes the viscosity behavior more be difficult to set lacquer, and the change of prescription is had serious result for viscosity behavior.

If by using the derivatived cellulose with low chain length to improve shear viscosity particularly with bigger amount, then prescription is more promptly determined in expection.Yet, be expensive to the solution of this problem, because the ether of cellulose that it must be relatively large.

Be used for the satisfied requirement of HEC of emulsion paint, and MHEC provides this required high shear viscosity of the user about high shear viscosity.

Another correlated variables for practice is the hot flock point of the plain derivative of some fibre.The effect of hot flock point is in water, is being higher than for the typical temperature of derivatived cellulose the derivatived cellulose water fast that becomes.Because in preparation manipulation or in the process of transporting subsequently, storing or use, emulsion paint may fully be exposed to the temperature up to 65 ℃, so importantly the flock point of derivatived cellulose is higher than 65 ℃ at least.This guarantees and enough distances of the temperature that runs into of typical case in practice.

The HEC and the MHEC that are used for emulsion paint satisfy this requirement.HEC does not have hot flock point in water.The hot flock point of MHEC that is used for emulsion paint is usually above 70 ℃.Yet other derivatived cellulose that has hot flock point in water for example MHPC can not be implemented in extensive enforcement on the market, because they have the hot flock point less than 70 ℃.

The use of MHEHPC also is known for the technician.US 3,873, and 518 to have described methoxy content be that 6-12.5 weight %, hydroxyl-oxethyl content are that 10-22 weight % and hydroxyl hydroxypropoxyl content are the MHEHPC of 14-32 weight %, and they are as the purposes of thickening material in the emulsion paint.Be higher than 70 ℃ flock point although they have, these products have with HEC about the identical shortcoming of low shear viscosity.

EP 0 598 282 has described the substitution value of hydroxyalkyl less than 0.7, and is more special in 0.3 especially less than 0.6, and the substitution value of methyl is 1.6 to 2.5, is more particularly 1.8 to 2.4 MHEHPC that described MHEHPC is as the thickening material that is used for pickling agent.

It is 0.9 to 2.1 that EP 0 120 430 has described the degree of methylating, and the hydroxyethyl degree is 0.2 to 0.5, and the hydroxypropyl degree is 0.08 to 0.4 MHEHPC.These products have the flock point less than 70 ℃.

Not only the product of the product of EP 0 598 282 but also EP 0 120 430 all has high surperficial swelling and produces the product of flock point＜70 ℃.

Usually, ether of cellulose can obtain by following method: with alkali metal hydroxide aqueous solution Mierocrystalline cellulose is alkalized, make the Mierocrystalline cellulose and the reaction of one or more epoxy alkane of alkalization, and/or with the reaction of one or more haloalkanes, if and suitably, resulting ether of cellulose is separated from reaction mixture, with its cleaning be dried, and it is pulverized.

As mentioned, it is known having the dissolved of delay ether of cellulose itself; Referring to, for example, Ullmann industrial chemistry encyclopaedia (Ullmann ' s Encyclopaedia of TechnicalChemistry), A5 volume, 472-473 page or leaf.

Have and postpone the dissolved ether of cellulose according to prior art for preparing, for example by to separating and the ether of cellulose of purifying adds oxalic dialdehyde from reaction mixture, this adding occur in grind and drying before, and carry out crosslinked.EP 1 316 563 has described this type of and has been used to postpone the dissolved method.

The etherification method that is used to prepare mixed cellulose ethers is prior art normally, and for example is described among the EP 1 180 526 and EP 1 279 680.

Owing to do not have known derivatived cellulose to satisfy above-indicated whole requirement so far, continue to exist to provide to have pressing for of following derivatived cellulose:

Under in addition condition not, demonstrate low surperficial swelling in aqueous dispersion with post-processing step to powdered product;

Demonstrate high shear viscosity as the aqueous solution; With

In water, have and be higher than 65 ℃ hot flock point at least.

Now by using following ternary derivatived cellulose can realize this purpose surprisingly: have specific replacement and dimethyl hydroxyethyl hydroxypropylcellulose (MHEHPC) about hydroxyethyl, hydroxypropyl and methyl.

In the ether of cellulose chemistry, usually, alkyl replaces to be described by DS.DS is the mean number by the replacement OH base of each anhydroglucose unit.Methyl substituted is expressed as for example DS (methyl) or DS (M).

Typically, the hydroxyalkyl replacement is represented by MS.MS is the anhydroglucose unit by every mole, with the average mol of the form bonded etherifying reagent of ether.Use the etherificate of etherifying reagent oxyethane to be reported as for example MS (hydroxyethyl) or MS (HE).Correspondingly, use the etherificate of etherifying reagent propylene oxide to be called MS (hydroxypropyl) or MS (HP).

Determining of side group, promptly for MS and DS value really normal root carry out according to Zeisel's method (reference: G.Bartelmus and R.Ketterer, analytical chemistry magazine (Z.Anal.Chem.) 286 (1977) 161-190).

The present invention at first provides following MHEHPC.

MHEHPC of the present invention has 0.10 to 0.70, preferred 0.15 to 0.70, more preferably 0.20 to 0.65 MS (HE); 0.30 to 1.00, preferred 0.30 to 0.90, more preferably 0.35 to 0.80 MS (HP); With 1.15 to 1.80, preferred 1.20 to 1.75 DS (M).

Particularly preferably be, MHEHPC of the present invention has 0.24 to 0.60, more preferably 0.27 to 0.55 MS (HE), and 0.41 to 0.75, more preferably 0.42 to 0.70 MS (HP) and 1.22 to 1.70, more preferably 1.25 to 1.65 DS (M).

Particularly preferably be, MHEHPC of the present invention has 0.29 to 0.50 MS (HE) and 0.44 to 0.65 MS (HP), and 1.30 to 1.60 DS (M).

Total hydroxyalkylation MS (HA) degree of MHEHPC of the present invention equals MS (HE) and adds MS (HP), is generally 0.45 to 1.60, and is preferred 0.55 to 1.5, and more preferably 0.65 to 1.4, be preferably 0.70 to 1.30 especially.

For based on the amount of 2 weight % of solution and the shearing rate of 2.55l/s, can be 100 to 200 000mPas in the viscosity of the solution of the MHEHPC of the present invention of 20 ℃ of measurements in water.Preferably use viscosity be 1000 to 80 000mPas, more preferably be higher than 30 000 to 80 000mPas, particularly preferably in the MHEHPC grade between 35 000 to 70 000mPas.The scope with low surperficial swollen HEC product that can get for the user is 3000 to 30 000mPas so far.Because MHEHPC of the present invention, 30 000 to 80 000mPas, the more preferably scope of the viscosity higher between 35 000 to 70 000mPas have also been opened now.Viscosity is determined in above-mentioned concentration and in the measurement of the aqueous solution of specific shearing rate at 20 ℃ according to DIN 53019 by use measuring sensor in HaakeRotovisko VT 550.

Ether of cellulose of the present invention is typically with granularity x ₅₀Powder type between 50 to 500 μ m uses.Granularity x ₅₀The material therefor that is defined as 50 weight % is at least the granularity of x less than x and 50 weight %.Preferably, all particles are by 300 μ m sieve, and this determines by the screen analysis according to DIN66165 in each case.

Ether of cellulose of the present invention can be used as mixture and uses or be used in combination with other cellulose base thickening material or synthetic thickening agent.

Ether of cellulose of the present invention preferably is given dissolving-retard formulation.This expression ether of cellulose is water-insoluble temporarily by for example reversible crosslink.By contacting with water, the ether of cellulose particle does not enter solution, but can initially disperse slightly.Cause dissolving by for example improving temperature or changing pH then.Being used to postpone a kind of preferred reagent of dissolved is oxalic dialdehyde, and it is attached in the ether of cellulose by art methods or coats the surface.

Ternary ether of cellulose of the present invention demonstrates the low surperficial swelling in aqueous dispersion.The surface swelling is illustrated in derivatived cellulose and does not enter under the condition in the solution, and water is by the derivatived cellulose physical bond.Under the situation of small-particle, can not distinguish the surperficial swelling and the particle swelling as a whole of particle in some cases at this.

Determine by a kind of special practical methods of surperficial swollen that swelling value is represented it is the dense slightly acidic suspension of preparation ether of cellulose, observe agitatability then.Concentration of slurry at 14g, preferred 16g ether of cellulose/100ml water still can stir 1 minute according to product of the present invention at least.For described method, what must guarantee is the physical bond of measuring water.This can be by for example fully postponing to realize via the crosslinked dissolved of oxalic dialdehyde.By the setting of slightly acidic pH, the dissolving of the ether of cellulose of handling through oxalic dialdehyde then is prevented from.Determine that the exact method of swelling value describes in an embodiment.

Ether of cellulose of the present invention has usually at 500s ^-1Shearing rate be at least the high shear viscosity (V of 270xmPas ₅₀₀).At this, x is in order to prepare at 2.55s ^-1Shear viscosity characterization (V _{2.55 (x)}) for the cellulose ether aqueous solution of 9500-10 500mPas institute must use, in amount based on the weight % of complete soln.Condition V ₅₀₀〉=270xmPas does not need to run through V _2.55(x)=9500 use to the entire area of 10 500mPas.If for a value x, obtain being in the viscosity V in the scope of 9500 to 10 500mPas _{2.55 (x)}, then be enough.

At this, the viscosity in aqueous solution that shear viscosity is represented derivatived cellulose determines in the shearing rate of 500l/s, this solution the viscosity of 2.55l/s by suitable amount be adjusted to 10 000mPas+/-500mPas.Under the condition that emulsion paint did not totally become sticking, be worth the shear viscosity in the emulsion paint is maximized; In other words, the viscosity of system should not be higher than for example 9500-10 500mPas.

Because in preparation manipulation or in the process of transporting subsequently, storing or apply, emulsion paint may be exposed to the temperature up to 65 ℃ fully, and the flock point of highly suitable is derivatived cellulose is higher than 65 ℃ at least.This guarantees and the typical in practice enough distances of temperature that run into.Hot flock point in water represents that the derivatived cellulose in the solution in water leaves dissolved state when the temperature of ether of cellulose solution raises.There is the considerable change of the character of ether of cellulose/aqueous systems at this point.These change of properties can for example be passed through rheology or optical measurement.The variation of rheological property for example may cause the destruction of stabilising dispersions so far in the emulsion paint system, thereby causes lacquer to become and can not use.Ether of cellulose of the present invention has in water and is higher than 65 ℃, preferred at least 70 ℃, more preferably at least 72 ℃ hot flock point (being flocculation temperature).The exact method of measuring flocculation temperature is described in an embodiment.

The method that the present invention is used to prepare new ternary ether of cellulose comprises the following steps:

A) plain the using by each anhydroglucose unit (AGU) 1.5 to 5.5 normal alkali metal hydroxides of original fibers alkalized, described alkali metal hydroxide preferably uses with the form of the alkyl metal hydroxides aqueous solution,

B) make from the alkalization Mierocrystalline cellulose of step a) and oxyethane and propylene oxide and in the presence of suspension medium, react in the temperature that is higher than 65 ℃, described suspension medium comprises haloalkane with the amount A that calculates according to following formula, A=[subtracts 1.4 by the equivalent of the alkali metal hydroxide of each AGU] to [equivalent by the alkali metal hydroxide of each AGU adds 0.8]

C) be metered into other haloalkane with amount B then, poor by between the amount of the alkali metal hydroxide of each AGU that described amount B is at least the normal amount A of the haloalkane by each AGU that has been metered into and has been metered into, this amount B is not less than 0.2 equivalent by each AGU

D) if be fit to, be higher than 65 ℃ add other alkali metal hydroxide and

E) resulting alkyl-hydroxyalkylcelluloswith is separated from mixture of reaction products, and if necessary, with its cleaning.

Proper raw material is the Mierocrystalline cellulose of mechanical pulp or velveteen form.The soltion viscosity of etherificate product can change in wide region by suitable selection original fibers element.What have preferred well-formedness is grinding machinery paper pulp and grinding lint cellulose or these mixture.

With polysaccharide with mineral alkali alkalization (activation), preferably with for example sodium hydroxide and potassium hydroxide alkalization (activation) of the alkali metal hydroxide in the aqueous solution, preferably with 35% to 60% intensity sodium hydroxide solution alkalization (activation), more preferably with 48% to 52% intensity sodium hydroxide solution alkalization (activation).

For example can use dme (DME), C as suspension medium ₅-C ₁₀Alkane such as hexanaphthene or pentane, aromatic substance such as benzene or toluene, alcohol as Virahol or the trimethyl carbinol, ketone such as butanone or pentanone, open chain or cyclic ether as glycol dimethyl ether or 1.4-diox and as described in the mixture of different ratios of suspension medium.Particularly preferred inertia suspension medium (suspension) can be dme (DME).

Provide the describe, in general terms of the method for using preferred inertia suspension medium DME below:

The Mierocrystalline cellulose that uses is used by each anhydroglucose unit (AGU) 1.5 to 5.5eqNaOH alkalization, preferably, more preferably used by each AGU 2.0 to 2.5eq NaOH and alkalize by each AGU 1.8 to 3.0eq NaOH alkalization.Generally speaking, alkalization is 15 to 50 ℃ temperature, and preferred about 40 ℃ temperature is carried out, and lasts 20 to 80 minutes, preferably lasts 30 to 60 minutes.The NaOH that uses is preferably the form of 35 to the 60 weight % intensity aqueous solution, the more preferably form of 48% to 52% intensity sodium hydroxide solution.

Subsequently the alkali cellulose that obtains is suspended in the mixture of the DME and first methyl chloride of measuring (MCl I).The measure feature of MCL I is as follows, and unit " eq " represents the mol ratio of each composition with respect to the cellulosic anhydroglucose unit (AGU) that adopts:

At least eq MCL I=subtracts 1.4 by the eq NaOH of each AGU, preferably subtracts 1.0, more preferably subtracts 0.6, and eq MCL I=adds 0.8 by the eq NaOH of each AGU at the most, preferably adds 0.5, more preferably adds 0.3.

The preferred amounts of MCL I is as follows: eq MCL I=subtracts 1.0 by the eq NaOH of each AGU at least, and same, and eq MCL I=adds 0.3 by the eq NaOH of each AGU at the most.

The special preferred amounts of MCL I is as follows: eq MCL I=subtracts 0.5 by the eqNaOH of each AGU at least, and same, and eq MCL I=adds 0.1 by the eq NaOH of each AGU at the most.

The most preferred amount of MCL I is as follows: eq MCL I=subtracts 0.5 by the eq NaOH of each AGU at least, and same, and eq MCL I=subtracts 0.1 by the eq NaOH of each AGU at the most.

Ratio DME/MCL I is generally 90/10 to 30/70 weight part, preferred 80/20 to 45/55 weight part, and more preferably 75/25 to 60/40 weight part.

After alkali cellulose being suspended in the DME/MCl mixture, being metered into hydroxyalkylation reagent oxyethane (EO) and propylene oxide (PO), and picking moving reaction by heating.The interpolation of hydroxyalkylation reagent can also be carried out in the process of heating phase.Occur in 60 to 110 ℃ with the reaction of hydroxyalkylation reagent and MCL I, preferably at 70 to 90 ℃, more preferably at 75 to 85 ℃.

According to the target substitution level, the EO that use amount is for by each AGU 0.20 to 3.25eq, preferably by each AGU 0.38 to 1.85eq, more preferably by each AGU 0.48 to 1.30eq.In a metrology steps, join EO in the reaction system or in two above metrology steps portioning join in the reaction system, if suitable and the PO that will measure join in the reaction system simultaneously or with the form with the mixture of the PO that will measure.Alternatively, the adding of EO and PO can also take place successively, and in this case, order can change.

According to the target substitution level, the PO that use amount is for by each AGU 0.44 to 4.00eq, preferably by each AGU 0.53 to 2.35eq, more preferably by each AGU 0.63 to 1.50eq.PO can occur in the metrology steps or portioning ground takes place in two above metrology steps to the interpolation of reaction system; Preferably be given in a step and measure, if suitable and the EO that will measure simultaneously or with the form of the mixture of the EO that will measure.

The continuous interpolation of the maximum mixture that preferably gives EO and PO.

In first etherificate after the stage, at the methyl chloride (MCL II) that does not have to add under the essence refrigerative condition for the second required amount of the methyl substituted of expectation, feature of this second amount is as follows: eqMCL II=eq NaOH subtracts eq MCL I and adds 0.3 at least, if or the amount of the MCL II that calculates by following formula is less than by each AGU 0.2eq MCL, then at least eq MCL II=by the 0.2eq MCL of each AGU.Preferably be given and use eq MCL II=by each AGU 1 to 3.5eq MCL, more preferably eq MCL II=is by each AGU 1.5 to 2.5eq MCL.The MCL II of described amount is added in the temperature that is higher than 65 ℃, preferably add 75 to 90 ℃ temperature, or the temperature adding of general (prevails) when the hydroxyalkylation stage finishes.

Subsequently, in order to set high DS (M), randomly, be metered in the form of the alkali metal hydroxide that does not have to measure in addition under the essence refrigerative condition with the aqueous solution.Preferably use the NaOH of 35 to 60 weight % intensity aqueous solution forms, more preferably use the NaOH of 48% to 52% intensity sodium hydroxide solution form.Preferably use by each AGU 0.2 to 1.9eq NaOHII in the form of adding subsequently; Especially preferably use by each AGU 0.4 to 1.5eq NaOH II in the form of adding subsequently; Most preferably use by each AGU 0.6 to 1.1eq NaOH II in the form of adding subsequently.

After the second etherificate stage finished, go out all volatile constituents by fractionation by distillation, if be fit to then use decompression to distill.The purifying of resultant product, drying and grinding are carried out according to typical prior art method in the cellulose derivative technology.

Embodiment

Following mensuration flocculation temperature: will be heated above 95 ℃ temperature with the heating rate of 2 ℃/min and under (magnetic stirring apparatus) condition of stirring based on the test water solution that complete soln contains the ether of cellulose of 0.1 weight %.The device that uses is the circulation thermostat that has temperature program(me) setting apparatus, cooling module and be used for the heat-transfer medium of 20 to 130 ℃ of temperature, has the Controllable Temperature stirred vessel of dual chuck in addition, and described container is connected with thermostatted.By mode in the photoabsorption of 450nm, use waveguide photometer 662 (waveguide photometer 662) (Metrohm) to measure by the muddiness (clouding) due to the flocculation of ether of cellulose, and with the thermograph of muddiness with respect to solution.Branch for the graphic representation that improves temperature gradually has more sharp-pointed bending (kink), and this indicates flock point, thereby indicates flocculation temperature.Article one, tangent line is near baseline, and another is by the absorption temperature point of inflexion on a curve.In the insertion point of tangent line, flocculation temperature reads out to 0.1 ℃.Rule of thumb limit of error is about ± 0.3-± 0.5 ℃.

Viscosity is by in having the Haake Rotovisko VT 550 of measuring sensor, according to DIN53019, and at 20 ℃, described concentration and measure the aqueous solution and measure under various situations with described and shearing rate in all cases.

The following mensuration of swelling value: in 400ml glass beaker (high type) with the tap water of 100.00g at about 3 minutes with interior NaH with 0.200g ₂PO ₄Dissolving (visual inspection) fully.With the room temperature of solution in 20+/-0.5 ℃, (40 * 8mm) are initially at the 500rpm stirring to use commercial magnetic stirring apparatus (for example from IKA:IKA RET basic (basic) or IKAMAG RET) to use the magnetic force splash bar of commercial teflon (Teflon)-coatings.Afterwards, at time t=0 (stopwatch), at first the ether of cellulose of handling through oxalic dialdehyde under study for action with 2.000g adds rapidly at the middle part on glass beaker surface.According to method, handle ether of cellulose with oxalic dialdehyde according to the embodiment 5 of the 4-5 page or leaf of EP1316563A1.Then,, add the ether of cellulose of other 2.000g, regulate the speed that promptly improves magnetic stirring apparatus every 60 seconds.When suspension no longer can stir, stop test.At least in some cases, this is to keep stopping the situation of lasting from the teeth outwards more than 1 minute when ether of cellulose.The maximum that can disperse the ether of cellulose that promptly still can stir is corresponding to the summation of the amount by stirring the ether of cellulose that bonded progressively adds fully, until and comprise the amount of last adding.The certain proportion of addition is ignored, and the certain proportion of this addition may be disperseed, but the remainder of this addition no longer can be by stirring combination.After adding 14g, preferred 16g, finish test.Swelling is enough low in this case.

About flocculation temperature and swollen embodiment

Be apparent that from the following embodiment of the invention 4 to 9 and comparative example 1 to 3 and 10 to 12 MHEHPC of the present invention not only has fully high flocculation temperature, also has good swelling value.

Embodiment	??DS?M	??MS?HE	??MS?HP	??V2??mPa·s	Flocculation temperature ℃	Swelling value g
							Comparative example 1	??1.1	??0	??1.04	??37?000	??65	??12
Comparative example 2	??1.1	??0.13	??1.12	??34?000	??65	??≥16
							Comparative example 3	??1.41	??0	??0.4	??39?600	??69	??10
The embodiment of the invention 4	??1.42	??0.11	??0.42	??38?700	??70	??14
							The embodiment of the invention 5	??1.42	??0.25	??0.41	??37?800	??72	??≥16

Embodiment	??DS?M	??MS?HE	??MS?HP	??V2??mPa·s	Flocculation temperature ℃	Swelling value g
							The embodiment of the invention 6	??1.44	??0.37	??0.45	??67?300	??73	??≥16
The embodiment of the invention 7	??1.41	??0.39	??0.43	??38?200	??74	??≥16
							The embodiment of the invention 8	??1.35	??0.40	??0.48	??56?100	??76	??≥16
The embodiment of the invention 9	??1.22	??0.44	??0.57	??55?100	??80	??≥16
							Comparative example 10	??1.33	??0.32	??0.18	??81?000	??84	??6
Comparative example 11	??1.34	??0.31	??0.09	??85?000	??86	??10
							Comparative example 12	??1.36	??0.32	??0	??92?000	??91	??8

Similarly, by Natvosol (HEC) and and Type 3U (EHEC) realized good swelling value.Yet these have low shear viscosity.

Embodiment about shear viscosity

Be apparent that in Fig. 1 compare with MHPC and also compare with MHEHPC of the present invention with MHEC, HEC, hmHEC (hydrophobic modified HEC), CMC and EHEC demonstrate the shortcoming of lower shear viscosity.

??CRT?40?000?PV	??1.20	??10?236	??280	??233	Not
						??CRT?20?000?PV	??1.70	??9?890	??310	??183	Not
??CRT?10?000?PV	??1.80	??9?809	??416	??231	Not
						??CRT?3000?PV	??2.80	??10?170	??626	??224	Not
??Celflow?S-200	??1.60	??10?471	??375	??234	Not
						??Celflow?S-50	??2.70	??10?006	??584	??216	Not
HmHEC (comparison)
						??Natrosol?plus?330?PA/1(TCS)	??2.60	??9.030	??325	??125	Not
??Natrosol?plus?330?PA/2(TCS)	??2.65	??9?693	??337	??127	Not
						??Natrosol?plus?330?CS	??2.60	??10?380	??393	??151	Not
??Natrosol?plus?430?PA	??1.20	??9?873	??145	??121	Not
						??Tylose?E?60210	??2.50	??9?681	??371	??148	Not
??Tylose?E?60302	??1.50	??9?929	??233	??155	Not
						??MHEHPC

??CRT?40?000?PV	??1.20	??10?236	??280	??233	Not
						The embodiment of the invention 5	??1.35	??11?160	??407	??302	Be
The embodiment of the invention 8	??1.10	??9?712	??314	??285	Be
						The embodiment of the invention 9	??1.10	??10?250	??306	??278	Be
Comparative example 13	??1.45	??9?730	??382	??263	Not

Comparative example 13 and MHEHPC of the present invention according to US 3873518 (Strange etc.) have following substitution value:

Embodiment	??DS?M	??MS?HE	??MS?HP
				The embodiment of the invention 5	??1.42	??0.25	??0.41
The embodiment of the invention 8	??1.35	??0.40	??0.48
				The embodiment of the invention 9	??1.22	??0.44	??0.57
Comparative example 13	??1.12	??0.5	??1.05

Preparation embodiment

In the 400l autoclave, make the grinding machinery paper pulp of 24.7kg and the grinding velveteen of 10.4kg become inertia by emptying with the nitrogen covering.Subsequently, the mixture with the methyl chloride of the dme of 57.4kg and 1.9mol eq is metered in the reactor.Then, under condition of stirring, in about 10 minutes, the sodium hydroxide of 2.2mol eq is ejected on the Mierocrystalline cellulose with 50 weight % intensity aqueous sodium hydroxide solution forms.In the whole process of step of reaction, reaction system continues mixed.Alkalization was carried out other 35 minutes.The metering of hydroxide solution and alkalization are subsequently proceeded to be subjected to raise from about 25 ℃ of extremely about 40 ℃ temperature.Then in about 30 minutes, the oxyethane of 0.60mol eq is metered in the reactor.Subsequently in about 35 minutes, the propylene oxide of 1.05mol eq is metered in the reactor.In the process that the metering of epoxy alkane is added, mixture is heated to about 80 ℃ lentamente.When being blended in this temperature and having carried out other 40 minutes, proceed to about 85 ℃ at 15 minutes internal heating, in 10 minutes, the methyl chloride of 2.20mol eq is metered in the reactor then.In this temperature, continue reaction 50 minutes more subsequently.Reactor afterwards distills out volatile constituent and find time.

Use hot water crude product to be washed dry granulation and grinding then.In the process of granulation step, in conjunction with being the oxalic dialdehyde of 1 weight % based on dried MHEHPC quality.

Resulting dimethyl hydroxyethyl hydroxypropylcellulose is 1.41 by the substitution value (DS M) of methyl, is 0.39 by the substitution value (MS HE) of hydroxyethyl, and is 0.43 by the substitution value (MS HP) of hydroxypropyl.

The soltion viscosity of this ether of cellulose in water is under the situation of 2 weight % in the amount of using, and is 38200mPas during in the shearing rate of 2.55l/s, 20 ℃ of measurements.

Claims (9)

1. dimethyl hydroxyethyl hydroxypropylcellulose (MHEHPC) is characterized in that 0.10 to 0.70 MS (HE), 0.30 to 1.00 MS (HP) and 1.15 to 1.80 DS (M).

2. according to the MHEHPC of claim 1, in the scope of its viscosity between 100 to 200000mPas.

3. according to the MHEHPC of claim 1 or 2, total hydroxyalkylation degree MS (HE)+MS (HP) is 0.45 to 1.60.

4. according to each MHEHPC in the aforementioned claim, described MHEHPC exists with the powder type of granularity between 50 to 500 μ m.

5. according to each MHEHPC in the aforementioned claim, the swelling value of described MHEHPC is at least 14g.

6. according to each MHEHPC in the aforementioned claim, the flocculation temperature of described MHEHPC is higher than 65 ℃.

7. according to the MHEHPC of claim 6, described MHEHPC has V ₅₀₀The shear viscosity of 〉=270xmPas, x represents in order to prepare at 2.55s ^-1The viscosity (V of shearing rate _{2.55 (x)}) for the MHEHPC aqueous solution of 9500-10500mPas needed in amount based on the MHEHPC of the weight % of complete soln.

8. be used for preparing according to each the method for MHEHPC of aforementioned claim, wherein

A) the original fibers element is used 1.5 to 5.5 normal alkali metal hydroxide alkalization by each AGU,

B) make from the alkalization Mierocrystalline cellulose of step a) and oxyethane and propylene oxide in the temperature that is higher than 65 ℃, in the presence of suspension medium, react, described suspension medium comprises haloalkane with amount A, described amount A=[subtracts 1.4 by the equivalent of the alkali metal hydroxide of each AGU] to [equivalent by the alkali metal hydroxide of each AGU adds 0.8]

C) be metered into other haloalkane with amount B then, poor by between the amount of the alkali metal hydroxide of each AGU that described amount B is at least the normal amount A of the haloalkane by each AGU that has been metered into and has been metered into, this amount B is not less than 0.2 equivalent by each AGU

D) if be fit to, be higher than 65 ℃ add other alkali metal hydroxide and

E) resulting alkyl-hydroxyalkylcelluloswith is separated from mixture of reaction products, and if necessary, with its cleaning.

9. according to each the purposes of MHEHPC in dispersion bonded material of construction system in the claim 1 to 7.

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